Graf oneAdvanced Operation Manual page 19

Once step is complete, the cleaning process starts again with step 1.
2 cycles are undertaken a day. The maintenance company can individually adapt the switching
times.
3.2.4.2 Process flow of oneAdvanced larger than 10 PE
The process is a series of 5 steps undertaken in turn and repeated several times a day (usually
four times).
Step 2: Settle
There is no aeration in the second phase. The aerated sludge and the re-
maining settleable solids can now settle with the aid of gravity. A clear wa-
ter zone forms at the top and a sludge layer at the bottom. Any floating
sludge is on top of the clear water zone.
Step 3: Clear water extraction
In this phase, the biologically cleaned wastewater (clear water) is drawn out
of the SBR stage. It is pumped out by an air lift (or mammoth) pump, which
uses compressed air. The air lift pump is designed not to pump out any
floating sludge on top of the clear water layer. A minimum water level is
maintained in the system without any further components.
Step 1:
The raw wastewater held in the sludge reservoir is fed to the
SBR reactor via an air lift pump. This is arranged such that
only water free of solids is pumped. The special design of the
lifter guarantees a minimum water level in the sludge reser-
voir.
Duration: approx 5–20 min
3. General
Feed
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